Functions
struct nfulnl_msg_packet_hdr *	nflog_get_msg_packet_hdr (struct nflog_data *nfad)

uint16_t	nflog_get_hwtype (struct nflog_data *nfad)

uint16_t	nflog_get_msg_packet_hwhdrlen (struct nflog_data *nfad)

char *	nflog_get_msg_packet_hwhdr (struct nflog_data *nfad)

uint32_t	nflog_get_nfmark (struct nflog_data *nfad)

int	nflog_get_timestamp (struct nflog_data nfad, struct timeval tv)

uint32_t	nflog_get_indev (struct nflog_data *nfad)

uint32_t	nflog_get_physindev (struct nflog_data *nfad)

uint32_t	nflog_get_outdev (struct nflog_data *nfad)

uint32_t	nflog_get_physoutdev (struct nflog_data *nfad)

struct nfulnl_msg_packet_hw *	nflog_get_packet_hw (struct nflog_data *nfad)

int	nflog_get_payload (struct nflog_data nfad, char *data)

char *	nflog_get_prefix (struct nflog_data *nfad)

int	nflog_get_uid (struct nflog_data nfad, uint32_t uid)

int	nflog_get_gid (struct nflog_data nfad, uint32_t gid)

int	nflog_get_seq (struct nflog_data nfad, uint32_t seq)

int	nflog_get_seq_global (struct nflog_data nfad, uint32_t seq)

Detailed Description

Function Documentation

int nflog_get_gid	(	struct nflog_data *	nfad,
		uint32_t *	gid
	)

nflog_get_gid - get the GID of the user that has generated the packet

Parameters

nfad	Netlink packet data handle passed to callback function

Returns: the GID of the user that has genered the packet, if any.

Definition at line 831 of file libnetfilter_log.c.

uint16_t nflog_get_hwtype ( struct nflog_data * nfad )

nflog_get_hwtype - get the hardware link layer type from logging data

Parameters

nfad	pointer to logging data

Returns: the hardware link layer type.

Definition at line 633 of file libnetfilter_log.c.

uint32_t nflog_get_indev ( struct nflog_data * nfad )

nflog_get_indev - get the interface that the packet was received through

Parameters

nfad	Netlink packet data handle passed to callback function

Returns: The index of the device the packet was received via. If the returned index is 0, the packet was locally generated or the input interface is not known (ie. POSTROUTING?).

Warning: all nflog_get_dev() functions return 0 if not set, since linux only allows ifindex >= 1, see net/core/dev.c:2600 (in 2.6.13.1)

Definition at line 706 of file libnetfilter_log.c.

struct nfulnl_msg_packet_hdr* nflog_get_msg_packet_hdr ( struct nflog_data * nfad )

nflog_get_msg_packet_hdr - return the metaheader that wraps the packet

Parameters

nfad	Netlink packet data handle passed to callback function

Returns: the netfilter log netlink packet header for the given nflog_data argument. Typically, the nflog_data value is passed as the 3rd parameter to the callback function set by a call to nflog_callback_register().

The nfulnl_msg_packet_hdr structure is defined in libnetfilter_log.h as:

        struct nfulnl_msg_packet_hdr {
                uint16_t       hw_protocol;    // hw protocol (network order)
                uint8_t        hook;           // netfilter hook
                uint8_t        _pad;
        } __attribute__ ((packed));

Definition at line 621 of file libnetfilter_log.c.

char* nflog_get_msg_packet_hwhdr ( struct nflog_data * nfad )

nflog_get_msg_packet_hwhdr - get the hardware link layer header

Parameters

nfad	pointer to logging data

Returns: the hardware link layer header

Definition at line 655 of file libnetfilter_log.c.

uint16_t nflog_get_msg_packet_hwhdrlen ( struct nflog_data * nfad )

nflog_get_hwhdrlen - get the length of the hardware link layer header

Parameters

nfad	pointer to logging data

Returns: the size of the hardware link layer header

Definition at line 644 of file libnetfilter_log.c.

uint32_t nflog_get_nfmark ( struct nflog_data * nfad )

nflog_get_nfmark - get the packet mark

Parameters

nfad	Netlink packet data handle passed to callback function

Returns: the netfilter mark currently assigned to the logged packet.

Definition at line 666 of file libnetfilter_log.c.

uint32_t nflog_get_outdev ( struct nflog_data * nfad )

nflog_get_outdev - gets the interface that the packet will be routed out

Parameters

nfad	Netlink packet data handle passed to callback function

Returns: The index of the device the packet will be sent out. If the returned index is 0, the packet is destined for localhost or the output interface is not yet known (ie. PREROUTING?).

Definition at line 732 of file libnetfilter_log.c.

struct nfulnl_msg_packet_hw* nflog_get_packet_hw ( struct nflog_data * nfad )

nflog_get_packet_hw - get hardware address

Parameters

nfad	Netlink packet data handle passed to callback function

Retrieves the hardware address associated with the given packet. For ethernet packets, the hardware address returned (if any) will be the MAC address of the packet source host. The destination MAC address is not known until after POSTROUTING and a successful ARP request, so cannot currently be retrieved.

The nfulnl_msg_packet_hw structure is defined in libnetfilter_log.h as:

        struct nfulnl_msg_packet_hw {
                uint16_t       hw_addrlen;
                uint16_t       _pad;
                uint8_t        hw_addr[8];
        } __attribute__ ((packed));

Definition at line 772 of file libnetfilter_log.c.

int nflog_get_payload	(	struct nflog_data *	nfad,
		char **	data
	)

nflog_get_payload - get payload of the logged packet

Parameters

nfad	Netlink packet data handle passed to callback function
data	Pointer of pointer that will be pointed to the payload

Retrieve the payload for a logged packet. The actual amount and type of data retrieved by this function will depend on the mode set with the nflog_set_mode() function.

Returns: -1 on error, otherwise > 0.

Definition at line 789 of file libnetfilter_log.c.

uint32_t nflog_get_physindev ( struct nflog_data * nfad )

nflog_get_physindev - get the physical interface that the packet was received

Parameters

nfad	Netlink packet data handle passed to callback function

Returns: The index of the physical device the packet was received via. If the returned index is 0, the packet was locally generated or the physical input interface is no longer known (ie. POSTROUTING?).

Definition at line 719 of file libnetfilter_log.c.

uint32_t nflog_get_physoutdev ( struct nflog_data * nfad )

nflog_get_physoutdev - get the physical interface that the packet output

Parameters

nfad	Netlink packet data handle passed to callback function

The index of the physical device the packet will be sent out. If the returned index is 0, the packet is destined for localhost or the physical output interface is not yet known (ie. PREROUTING?).

Returns: The index of physical interface that the packet output will be routed out.

Definition at line 748 of file libnetfilter_log.c.

char* nflog_get_prefix ( struct nflog_data * nfad )

nflog_get_prefix - get the logging string prefix

Parameters

nfad	Netlink packet data handle passed to callback function

Returns: the string prefix that is specified as argument to the iptables' NFLOG target.

Definition at line 805 of file libnetfilter_log.c.

int nflog_get_seq	(	struct nflog_data *	nfad,
		uint32_t *	seq
	)

nflog_get_seq - get the local nflog sequence number

Parameters

nfad	Netlink packet data handle passed to callback function

You must enable this via nflog_set_flags().

Returns: the local nflog sequence number.

Definition at line 848 of file libnetfilter_log.c.

int nflog_get_seq_global	(	struct nflog_data *	nfad,
		uint32_t *	seq
	)

nflog_get_seq_global - get the global nflog sequence number

Parameters

nfad	Netlink packet data handle passed to callback function

You must enable this via nflog_set_flags().

Returns: the global nflog sequence number.

Definition at line 865 of file libnetfilter_log.c.

int nflog_get_timestamp	(	struct nflog_data *	nfad,
		struct timeval *	tv
	)

nflog_get_timestamp - get the packet timestamp

Parameters

nfad	Netlink packet data handle passed to callback function
tv	structure to fill with timestamp info

Retrieves the received timestamp when the given logged packet.

Returns: 0 on success, a negative value on failure.

Definition at line 680 of file libnetfilter_log.c.

int nflog_get_uid	(	struct nflog_data *	nfad,
		uint32_t *	uid
	)

nflog_get_uid - get the UID of the user that has generated the packet

Parameters

nfad	Netlink packet data handle passed to callback function

Returns: the UID of the user that has genered the packet, if any.

Definition at line 816 of file libnetfilter_log.c.

Functions

Detailed Description

Function Documentation